1. Field of the Invention
The present invention relates to an ink-jet recording device that ejects ink droplets from multiple nozzles onto a recording medium and records an image, and to a wiping method for the nozzle face of the ink-jet recording device.
2. Description of the Related Art
Conventional ink-jet recording devices that eject ink droplets from multiple nozzles and perform printing on a recording medium such as paper have various benefits, such as being compact, affordable, and quiet. Such printers are widely sold on the market. Recording devices of piezo ink-jet systems that use piezoelectric elements and eject ink droplets by changing the pressure of a pressure chamber have especially many assets, where high-speed printing and high resolution can be obtained.
In this type of ink-jet recording device, when the wiping of an ink-jet recording head (hereafter, “recording head”) is performed with a wiper, there is a danger of harming the nozzle surface if the wiping is performed when the wiper or recording head surface is in a dried state (i.e., dry wiping). Further, with dry wiping there is a problem in that fixed particles stuck to the recording head surface cannot be removed. On the other hand, when wiping directly after ink suction is performed for recovery from bubble engulfment and ink thickener, a large amount of ink remains on the nozzle surface. Accordingly, even if wiping is performed where the wiper is in a dried state, this becomes wet wiping, which does not pose aforementioned problems.
In a situation, for example, where faulty discharging occurs at a portion of the nozzles, the periphery of those nozzles becomes dirty. As a result, in a situation where faulty direction discharging occurs, suction of the ink is not necessary and the discharging condition can be recovered with the performance of wiping only. At this time, since dirtying by ink does not occur at nozzle peripheries separated by a certain distance from the faulty nozzles, if wiping is performed as is, the wiping at those nozzles becomes dry wiping, which is disadvantageous. In order to avoid this, the following approaches can be considered: (1) Performing wiping of the faulty nozzle(s) only; (2) Wetting the wiper itself; (3) Performing suction and wetting all of the nozzle faces; (4) Wetting the wiper by performing wiping while discharging (ink).
Nonetheless, it should be noted that approach (1) is not realistic in that mechanisms for establishing a method of specifying the faulty nozzle(s) and wiping only the specified nozzles become necessary. Approach (2) is not preferable since a mechanism for wetting the wiper becomes additionally necessary. Approach (3), despite a new mechanism not being especially necessary, is not preferable in that the amount of ink consumption increases, and approach (4) has a flaw in that the inside of the device is dirtied by ejected ink droplets.
Meanwhile, there have been proposals for means for removing ink stuck at the nozzle peripheries. For example, the application of waveform voltage that expands to the nozzle peripheries without discharging ink, and coalesces ink mist stuck to the nozzle peripheries and flooded ink, has been proposed. Here, back pressure and surface tension are used and the ink is suctioned into the interior of the nozzles (see, for example, the Official Gazette of Japanese Patent Application Laid-Open (JP-A) No. 3-293140).
Nonetheless, with the technique recited in the Official Gazette of JP-A No. 3-293140, only the nozzle peripheries are cleaned since wiping of the recording head with a wiper is not performed. Further, this has a flaw in that dirt besides ink such as paper particles are also suctioned into the interiors of the nozzles.